The present invention relates to an improved container for use in the commercial sale and distribution of eggs and to a novel method for packaging eggs. The present invention finds particular utility in providing a container which affords visibility of the eggs, yet offers a high level of protection against breakage.
In buying eggs, consumers generally open the lid of conventional opaque containers to look at the contents before making a purchase. On occasion, the contents of these conventional containers are exchanged with more expensive eggs from other containers, thus increasing the risk of damage both to the eggs and the container, while causing a corresponding loss to the supermarket.
Efforts at developing see-through egg containers of sturdy construction have heretofore not been entirely satisfactory. Currently used containers employing a clear plastic film or overwrap are susceptible to excessive egg breakage. Generally, these films are loosely formed over the upper surface of the eggs and are unable to retain the eggs fixedly in their preformed receptacle during handling of the container. Other methods sacrifice visibility for reduced vulnerability by providing a small hole in the container surface, exposing only a limited portion of the egg shell. The small hole does not permit adequate examination of the contents before purchase.
Some egg carton manufacturers make available containers having flaps which must be raised before wrapping the container with a plastic covering. These flaps are designed to offer some protection to the sides of the eggs. Since the natural disposition of the flaps is horizontal, there is a tendency for the flaps to return to that position. This causes the overwrap to stretch and become loose. Further, these flaps offer no protection to the top surface of the eggs, creating an obvious limitation on verticaly stacking the cartons.
Another problem existing in the prior art involves heat shrinking a plastic film onto the container for providing a tight seal. The heat shrinking process requires use of excessive heat, which can detract from the freshness and overall quality of the packaged eggs. Furthermore, when such plastic is handled, it becomes loose, thus increasing the potential for damage to the contents.
Covering an egg container with transparent wrapping ordinarily requires a considerable amount of plastic film material. In conventional practice, the film is wrapped around the entire container, i.e., bottom, top and sides. The amount of film currently used to envelop the eggs and the container is more than double the amount of film used by the present invention. On a volume basis, the amount of film used amounts to a considerable operating expense.
Present methods of packaging eggs also entail the use of preprinted containers for the purpose of identifying brand name, egg size and other data customarily provided in the marketing of eggs. A large egg processor servicing several egg distributors necessarily must maintain an extremely large supply of cartons. Storage space considerations and production costs of packaging products are constant marketing problems.
Accordingly, it is an object of the invention to provide a sturdy egg container permitting the consumer to view a substantial portion of the contents while also supporting the eggs in a way reducing potential breakage.
Another object of the present invention is the provision of a carton exposing a substantial portion of eggs for viewing while protecting both the sides and the top of the eggs so that the cartons may be vertically stacked.
Another object of the invention is the provision of an egg carton having upper sidewalls permanently biased to a vertical position preventing stretching of a plastic encasing film.
Another object of the present invention is covering the top surface of eggs in a carton with clear plastic forming a supporting surface retaining the eggs in place in an upright position.
Another object of this invention is securing a plastic supporting cover over eggs in a carton without use of excessive heat thereby ensuring a fresh product.
Another object of the present invention is applying a plastic film over the top and sides of the eggs to reduce the escape of carbon dioxide from the eggs, thereby preventing premature spoilage of the egg.
Another object of the present invention is minimizing the amount of plastic film used to envelop an egg carton while providing maximum egg supporting strength.
A further object of the present invention is the provision of an efficient method of packaging eggs reducing cost of production while simultaneously enhancing marketing flexibility.
A still further object of the present invention is the provision of a common egg carton capable of having any one of a number of various merchandising labels attached.
Additional objects and advantages of the invention will be set forth in part in the description which follows and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
To achieve the objects and in accordance with the purpose of the invention, as embodied and broadly described herein, the egg carton of this invention comprises a container having a plurality of cup-shaped receptacles aligned in a plurality of rows, each receptacle conforming to and adapted to receive a vertically positioned egg, a plurality of posts between the rows, a pair of upper sidewalls integrally hinged along hinge lines on opposite sides of the container, the upper sidewalls being normally biased toward a substantially horizontal position to permit placing eggs in the receptacle, the upper sidewalls having a sufficient length to extend at least to the outer edge of the first and last eggs in the rows and a height sufficient to extend above the upper ends of the eggs when the upper sidewalls are aligned in a vertical position, a hot sealing means applied to the hinge lines, the sealing means formed on the hinge line causing the upper sidewalls to remain in the vertical position, the container having a clear plastic film applied over and around upper portions of the eggs extending out of the container, the film being forced down around a portion of the eggs and adhering to the tops of the posts, and the film being secured to the hinge lines.
The present invention further includes a method of packaging eggs comprising the steps of providing a container having a plurality of receptacles receiving vertically positioned eggs, the container also having integrally hinged upper sidewalls normally biased in horizontal open positions along respective hinge lines on opposite sides of the container, the container further comprising a plurality of posts between the receptacles; placing eggs in each of said receptacles; pivoting the sidewalls toward a vertical covering position, partially covering the eggs, while leaving a substantial portion of the eggs exposed for viewing; applying a hot sealant along each of said hinge lines allowing said sidewalls to retain said vertical position; extruding a high speed plastic film at exposed portions of said eggs and said upper sidewalls and simultaneously applying a low vacuum to the container; and covering the upper exposed end portions of the eggs and sidewalls with a clear, thermally responsive plastic film. The method of the present invention also includes the steps of sealing the plastic film to the hinge lines; adhering the plastic film to a portion of the top of the posts; and attaching at least one label to a surface of one of the sidewalls.
The accompanying drawings, which are incorporated in and constitute part of this specification, illustrate one embodiment of the invention and, together with the description, serve to explain the principles of the invention.